Evaporative cooler



FIG. 1 is a rear elevational view of an evaporative cooler showing my new design;

FIG. 2 is a right side elevational view thereof; and

FIG. 3 is a left side elevational view thereof; and

FIG. 4 is a front elevational view thereof, as shown in one environment, the environment being in broken lines, the environment not being a part of the disclosed and claimed design; and

FIG. 5 is a top plan view thereof; and,

FIG. 6 is a bottom plan view thereof. 

The ornamental design for an evaporative cooler, as shown and described. 